1. Field of the Invention
This invention relates to a fusing device and a method for manufacturing a fusing member.
2. Description of Related Art
Conventionally, an image forming apparatus such as, e.g., a printer, a facsimile machine, or a photocopier is arranged with a fusing device to fuse toner images onto papers, in which the fusing device has a fusing roller or a fusing belt as a fusing member installed inside with a heater, as well as a pressure roller arranged to face to the fusing roller or the fusing belt.
In thus structured fusing device, for example, when a paper to which the toner image is transferred passes between the fusing roller and the pressure roller, the toner in the toner image is heated and melted with the fusing roller, thereby being pressed onto the paper with the pressure roller.
For stable operation of the above fusing, surface temperature of the fusing roller is detected, and fusing temperature for fusing the toner image is controlled based on the detected surface temperature (ref., e.g., Japanese Patent Application Publication No. JA2002-31,982).
In the above conventional fusing device, however, a thermistor needs to be arranged so as not to be parted from the surface of the fusing roller when used to detect the surface temperature of the fusing roller, so the thermistor rubs against the surface of the fusing roller while the fusing roller rotates.
FIG. 2 is an illustration for a state of the conventional fusing roller.
In the illustration, numeral 11 is a fusing roller, and when the fusing roller 11 is rotated as in contact with the thermistor, not shown, the thermistor rubs the surface of the fusing roller 11, thereby rendering surface roughness of the fusing roller 11 at a portion in contact with the thermistor rougher than that at other portions not in contact with the thermistor, and thereby strongly forming thermistor's traces E1 as abrasion traces in succession in a circumferential direction. Particularly, when the fusing roller 11 strongly formed with thermistor's traces E1 is used for solid printing, the thermistor's traces E1 are formed as gloss uneveness in printed results, so that the image quality is deteriorated.
It is an object of this invention to solve the above problems in the conventional fusing device and to provide a fusing device and a method for manufacturing a fusing member capable of improving the image quality upon preventing any abrasion trace from strongly forming on the surface of the fusing member.